The BIG bang behind Britain's iconic Spitfire & Hurricane, with firearms expert, Jonathan Ferguson

Published on October 25, 2023
Duration: 25:48

Expert Jonathan Ferguson, Keeper of Firearms & Artillery at the Royal Armouries, details the Hispano 20mm Cannon Mk.II, a pivotal WWII aircraft weapon. He covers its design, integration challenges in aircraft like the Spitfire, technical specifications including its 106 lb weight and 650-750 RPM rate of fire, and the evolution from problematic drum magazines to reliable belt-feed systems. The explanation highlights its gas-unlocked blowback operation and unique pneumatic firing mechanism.

Quick Summary

The Hispano 20mm Cannon Mk.II was a vital WWII aircraft auto cannon, weighing 106 lbs and firing 20mm shells with high destructive power. It evolved from problematic 60-round drum magazines to reliable 300-350 round pneumatic belt-feed systems and featured a unique gas-unlocked blowback operation managed by internal springs and muzzle brakes.

Chapters

  1. 00:00Introduction to the Hispano 20mm Cannon
  2. 00:35Defining the Auto Cannon
  3. 01:43Origins and Design
  4. 02:41Integration Challenges in Aircraft
  5. 06:56Technical Specifications and Firepower
  6. 09:44Feed Systems: Drum vs. Belt
  7. 13:07Recoil and Operating Mechanism
  8. 20:01Controls and Pneumatics

Frequently Asked Questions

What was the Hispano 20mm Cannon Mk.II used for?

The Hispano 20mm Cannon Mk.II was a critical auto cannon for British WWII fighter aircraft, designed to deliver high-explosive and semi-armor-piercing incendiary rounds capable of tearing large holes in enemy aircraft and vehicles.

Why was the Hispano 20mm Cannon so long?

The Hispano 20mm Cannon's considerable length, approximately 8 feet, was a design necessity to allow it to fire through the engine block of the Hispano-Suiza 12Y aero engine, a common integration method for aircraft armament of the era.

What were the main feed systems for the Hispano 20mm Cannon?

Early Hispano 20mm cannons used a 60-round drum magazine, offering limited firing duration. Later, more reliable versions adopted a pneumatic belt-drive system, significantly increasing ammunition capacity to 300-350 rounds per gun.

How did the Hispano 20mm Cannon manage recoil?

The Hispano 20mm Cannon employed a gas-unlocked blowback system causing the gun to recoil within the wing. Recoil was managed through complex internal spring systems and muzzle brakes to ensure operational stability.

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